Casing-shoe.



F. M. EDGAR & T. E. MoKBE.

CASING QHOE. APPLICATION FILED AUG. 20, 1912.

1,058,567.- Patented Apr. 8, 1913.

mue/wtow F M. E4 I E'- Mfl'ee fimwiflmazi UNITED STATES PATENT OFFICE.

FRANCIS M. EDGAR AND THOMAS E. MQKEE, OF SANTA PAULA, CALIFORNIA.

CASING-SHOE.

Specification of Letters Patent.

- Application filed August 20, 1912. Serial No. 716,051.

To all whom it may concern:

Be it known that we, FRANCIS M. EDGAR and THOMAS E. MCKEE, citizens ofthe United States, residing at Santa Paula, in the county of Ventura andState of California, have invented new and useful Improvements inCasing-Shoes, of which the following is a specification.

This invention relates to casin shoes used indrilling oil wells, thesame being fitted to the first oint of the casing put into the well.

In the ordinary makes of easing shoes now in common use, the teeth whichare provided on the bottom edge of the shoe are liable to become broken,and result in the breakage of other parts of the machinery, thus causingserious delay and expense. Furthermore, the lugs 01' cutters used onunder reamers, for example, soon become clogged with mud, during thereaming operation, makin it extremely hard to draw the reamer back intothe casing again.

The object of this invention is to provide a casing shoe which willovercome all of the objections now well understood by operators indrilling oil wells, and to provide a casing shoe'in which the cuttersare arranged so as to avoid any probability of the same becoming broken,while keeping the same in good cutting condition at all times.

With the above and other objects in view, the invention consists in theconstruction, combination and arrangement of parts, as will behereinafter more fully described, illustrated in the accompanyingdrawings, and pointed out in the claim hereunto appended. I In thedrawings: Figure 1 isa perspective view of a casing shoe embodying thepresent invention. Fig. 2 is a diametrical section through the same.Fig. 3 is a cross section through the casing shoe in linewith the teeth.

The casing shoe contemplated in this invention comprises essentially acylindrical body 1, internally threaded, as shown at 2, for attachmentto the casing, and internally Patented Apr. 8, 19130 beveled or roundedat its lower end, as shown aft 3.

On the outer face of the body, there is ar ranged a circular series ofcutting teeth 4, the opposite side edges of which are parallel to eachother, and undercut, as shown at 4, while the advance edge 5 thereof islikewise undercut, the rear or back edge thereof being beveled off, asshown at 6, so as to merge gradually into the outer face or periphery ofthe shoe, as clearly shown, thereby admitting of the easy reciprocationof the shoe. It will be observed that the spaces between the teeth areabout equal to the width of the teeth themselves, so as to give theproper clearance, and enable the shoe to be operated with ease.

In operation, the shoe is raised and lowered, and at the same time whileit is in an elevated position, it is turned, so as to shift the teeth toa diflferent cutting position. On account of the disposition, shape andarrangement of the teeth, the pipe or casing is allowed to followfreely.

What is claimed is:

A casing shoe, involving a hollow cylindrical body having the bottomedge thereof beveled internally and provided exteriorly with projectingcutting teeth having undercut side and front edges and beveled oil atthe top flush with the outside face of the body.

In testimony whereof we afix our signatures in presence of twowitnesses.

FRANCIS M. EDGAR. THOMAS E. MCKEE.

Witnesses:

G. L. UNDERWQOD, H. R. REoK.

